Cathode ray tube



April '19, 1938. B. HENSEL ET AL CATHODE RAY TUBE Filed July 26, 1934 AZI'TCBRNEY Patented Apr-.19, 1938 PATENT OFFICE 2,114,346 CATHODE RAY TUBE Bernhard Hansel, Kurt Hess, and Johann Richter,

Berlin, Germany, assignors to Teleiunken Gesellschaft iiir Drahtlose Telegraphic m. b. R, Berlin, Germany, a corporation of Germany Application -July 26, 1934, Serial No. 736,992 In Germany July 31, 1933 3Claims.

The invention relates to an electrode assembly in cathode ray tubes with electrostatic control and in which the deviation plates serving for the control of the coordinates are supported from the 5 press also serving for mounting the supporting wires of further electrodes, or the deviation plates are mounted on another part belonging to the electrode system.

In cathode ray tubes with electrostatic deviation of the coordinates two groups of electrodes are distinguishable. The one consists of the cathode and at least one anode and one control organ, while the second group is formed by the deviation plates. The mounting of these electrodes was hitherto carried out in two difierent ways. All electrodes have been mounted in a.

7 press and the connecting wires were passed through the press to the outside. This mounting noted by its simplicity has the disadvantage that so considerable coupling capacities exist between the two groups of electrodes, as a result of which the alternating voltages serving for the special deviation and for the intensity control disturb each other in such a manner that such tubes'are as useless for the television operation. For this reason, it has become a customary means to sealin the two electrode groups separate from each. other, in that cathode, anode and control organ are mounted in the press, while the deviation plates are independently therefrom mounted in the wall of the bulb, and the respective leads are laterally passed into the outside. The adjustment of the two groups of electrodes upon each other, which must be especially accurate in tele- 35 vision tubes, involves, however, difliculties and despite great care a completely accurate mounting cannot be assured.

The present invention makes possible a mechanically and electrically unobjectionable 4o mounting of the electrodes, in that the deviation plates are passed over small rods or tubes of insulating material fastened either to the press or to other parts of the electrode system. The supply lines to the deviation plates are sealed in 45. on the side of the neck of the bulb in the ordinary manner. This arrangement affords the mounting ofboth groups of electrodes in the press outside the tube and to obtain the required accuracy of the adjustment by the use of gauges. 50 In addition, the system of the deviation plates can be rendered-very stiil and therefore it is made insensitive against shocks and similar causes leading to deformation.

An embodiment of the invention is shown in 55 the drawing by way of example. In the corresponding Figs. la and lb the insulating rods are designated by i to 4 which may be of any desired section, for instance, round or square. 5, 6 and i, 8 are the respective deviation plates each provided on its back with two bushings or springs 9 5 to I2 and placed therewith over the insulating rods. Each plate has two bushings or springs and thus it is mounted on two insulating rods. The four insulating rods 6 to 6 are supported with respect to each other by the plates 5 to t and is joined so as to form a mechanically very stiff member. In order to render the plates stiii in themselves, the edge thereof can be cramped. The bushings 9 to I! may be formed of the same piece with the plate, whereby the manufacture 15 will be particularly simplified. The lead-ins i3, M, etc., to the deviation platesare sealed into the wall of the glass bulb from the side.

For the spacing of the pairs of deviation plates, bushings i5, iii of insulating material are used, 30 while the parts I! to serve for fixing the deviation plates in the axial direction. These parts may either be stiffened in the known manner'by means of insulating rods l to I, or if formed of glass they may be sealed.

In place of spacers l5 and IS, an insulating member may also be used which may for instance be formed as disk and which rests at least at two places on the wall of the bulb. As shown in Fig.

2, designatesa disk of insulating material congo taining four openings 3i to 34 adapted for the insulating rods l to l. A further opening 35 permits the passage of the electron ray. The disk 30 rests upon the wall of the bulb at the places 36 to 39 which may be correspondingly worked. 35 In this manner it is avoided that the insulating rods l to I may break due to an excessive. weight of the deviation plates.

Instead of fastening the supporting columns i to 4 in the press, the same may also be provided on another part of the electrode'system. Particularly suited therefor is the anode or a shielding cylinder which often surrounds the path .of the cathode ray extending between anode and deviation plate for the purpose of providing a shield against the detrimental influencesof wall charges. The insulating rods may, for instance.

. hereby be fastened to the inner or outer side of Having thus described the invention, what we claim is:

1. Cathode ray tube structure comprising a press for supporting the electrodes within the 5 tube, a plurality of insulating support members carried by the press, a. plurality of sets of electron beam deflecting plate electrodes a plurality of clamping members supported on the insulating members for positioning-and clamping the deflecting electrodes to each of the insulating members in predetermined position relative to each insulating member, and a conductor'connected with each deflecting electrode for 'applying voltages thereto.

'2. The electron tube structure claimed in claim 1 comprising in addition a disk-shaped insulat ing member supported by said insulating support -members and arranged to rest against the tube wall in at least two places.

0 3. In a cathode ray tube structure, a housing envelope having at one end thereof a press, a plurality of pairs of electron beam deflecting electrodes positioned in mutually perpendicular relationship, a plurality of insulating rod members supported in the press member, a clamping member attached to each of the insulating rod members, means for supporting each of the deflecting electrodes from the clamping members whereby each of the insulating rod members supports at least one deflecting electrode of each of the pairs of mutually perpendicular deflecting electrodes and the deflecting electrodes are positioned in fixed relationship with respect to each other, and conductor members connected to the deflecting electrodes for applying operating voltages thereto.

- B HENSEL.

KURT HESS. JOHANN RICHTER. 

